The big question for me is why, give that Manhattan has some of the most expensive real estate in the world, would you want to build a football stadium there? Especially when the Jets have a perfectly good stadium in New Jersey that would go empty if they leave. The whole thing is so incredibly wasteful, and as has been pointed out it's the taxpayers that would have paid for most of the waste.
The Yankees are building a new stadium too, but they're paying for the entire thing themselves. Good for them, I say.
On the Olympics, there was an editorial in the New York Times a few days back explaining why New York didn't need the Olympics. I can't find it now, but the gist of it was that the Olympics are valuable to highlight world cities that people might not otherwise think of. The Atlanta Olympics highlighted the success of the New South. Olympics in China and Greece will attempt to show that those nations have joined the modern world. More infamously, Hitler tried to use the Berlin Olympics to show that Germany had reemerged as a great power.
New York doesn't need this boost. Everyone knows New York already as the capital of commerce, culture, in many ways the capital of the world. New York has nothing to gain by hosting the Olympics.
Edit: and for full disclosure, I live in New Jersey, but I'm not a football fan so there's absolutley no conflict of interest involved
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